EDI components description and transport protocols presentation
EDI Components: sender and receiver
There are many EDI components involved in an EDI relationship between two trading partners. EDI is a batch process in which transactions are grouped together into one or more files and all transmitted at the same time. One trading partner is the sender (outbound) and one trading partner is the receiver (inbound). Both trading partners become senders and receivers throughout the relationship.
In most situations one trading partner is the driver of the EC/EDI relationship and the other trading partner is the follower. The driver can be a customer, industry association or government department, while the follower is a supplier, member of an association, or an organization that deals with the government. The driver will publish an implementation guide, companion guide or web site portal that describes its EDI program, procedures and expectations. Someone who is a supplier or deals with the government must become compliant by following the instructions set out in the guide. Members of an industry association are not mandated to use EDI, but they must follow the guide if they a going to implement EDI.
The following diagram depicts the flow of data between EDI components:
Data Transport is the process of electronically transferring files to/from your trading partners. Traditionally a Value Added Network (VAN) is used as the go-between for trading partners. The sender’s computer dials-up and drops off a file to the VAN, which in turn stores the file in an electronic mailbox. When the receiver’s computer is ready, it dials-up the VAN to pick up the files from the mailbox. Protocols such as Async and Bisync are used to securely transmit files to/from the VAN. Nowadays the Internet is used to make the connection to the VAN. It is also used to connect Point-to-Point to a trading partner, thus bypassing the VAN entirely. The computer dial-up step isn’t necessary if the Internet connection is always active, although some small businesses still use a dial-up Internet connection.
These are the most common protocols used to transmit files to/from a VAN or Point-to-Point:
File Transfer Protocol (FTP) – is initiated by either trading partner to transfer files to/from the VAN’s
computer, or Point-to-Point on the trading partner’s computer. It usually requires a log-in to gain access, but it is not fully secure because files are sent in clear text and could be intercepted and deciphered. File Transfer Protocol Secure (FTP/S) solves the problem by adding a level of security to thwart eavesdropping.
Hyper Text Transfer Protocol (HTTP) – is initiated by one trading partner to request files to be transferred from the VAN’s computer, or Point-to-Point from the trading partner’s computer. The receiver’s computer must acknowledge the request before sending the file. Hyper Text Transfer Protocol Secure (HTTP/S) is the same as HTTP, with an added level of security to encrypt files.
EDI-INT – is a set of standards for transferring EDI files through the Internet more securely than e-mail, FTP/S or HTTP/S. Applicability Statement 1 (AS1) defines the standards for using e-mail to transfer files, Applicability Statement 2 (AS2) defines the standards for using HTTP to transfer files and Applicability Statement 3 (AS3) defines the standards for using FTP to transfer files. While FTP/S and HTTP/S offer security, EDI-INT adds another layer of security involving public and private keys.